http://lime-technology.com/
UnRAID might do what you want.
Selectable folder duplication? Sure, OpenSolaris and ZFS can do that with ditto blocks.
Also you can have it combine any number of mirrored sets or RAIDZ groups together into one big pool even if the component mirrors / RAIDZs are of different sizes.
Actually any LINUX / UNIX can probably do a "raid like" thing with drives of different sizes, you just have to use partitions on those drives instead of physical drives so you have a little complexity to deal with in making a set of redundant and non-redundant partitions / raid volumes out of whatever mix of drives you have.
e.g. having drives A=100GB + B=200GB + C=300GB gives you
1 partition + 2 partitions + 3 partitions each of 100GB size.
So from those drives you could partition them to create all of the following at once..
A + B1 + C1 = 100GB + 100GB + 100GB which can be RAID5'd reliably.
B2 + C2 = 100GB + 100GB which can be mirrored reliably.
C3 = 100GB partition left over for non-redundant uses or to work in combination with some other partition for a mirror or raid or whatever.
Study up on LVM and MD/MDADM and you can do quite a bit of different things.
Originally posted by: ncage
Title pretty much says it all. Is there any type of software / file system in the *nix space that acts like WHS / Drobo to build a raid type system but allows you to mix / match drives to create a raid like system. Does it have selectable folder duplication like WHS?
thanks,
Ncage